In the concrete delivery industry, delivery of concrete to the job site often requires the delivery vehicle to be at a much different lateral distance and/or elevation than a particular region of the site that is to receive concrete. To overcome this obstacle concrete placement pumps are often employed to move the concrete over the distance required.
Within these concrete placement pumps, the concrete is pumped through a long tube affixed to the outlet of concrete placement pump moved to the delivery area for the concrete. To transport concrete through the steel tubing or hoses over the distance needed, large hydraulically driven piston pumps are used.
One of the most common modes of failure for the concrete trucks is an obstruction in the concrete pumping line. When an obstruction, occurs the system ceases to operate and no longer expels concrete to the region of interest. Unfortunately this effect behaves identically to other failure modes. If one of the controlling solenoids within the hydraulic drive develops a fault and no longer operates as desired, the drive will no longer be able to push the concrete pump. Once a failure mode occurs the crew must wait for a technician to arrive on the jobsite. Said technician can then begin troubleshooting this event to discover whether an obstruction in the line exists, or if the pumping system has a failed solenoid. Frequently, the issue is simply an obstruction; however time and resources are utilized to inquire the possibility of failed solenoid. Additionally, during time needed for the technician to arrive on site many times the concrete will harden causing serious damage to the concrete placement pump.
Oftentimes, the time required for an individual to reach the job site to troubleshoot and perform maintenance on the pumping system is too long. The concrete in the pump and the line will harden if left to sit too long. Once the concrete sets in this manner, the hardened concrete becomes incredibly difficult to remove. This costs a significant amount of time and recourses as well as the loss of time spent on the job site.
Another issue plaguing the concrete boom delivery industry is engine load during start up of the engine and on/off concrete pumping cycles during daily operation while concrete is in the pumping line. At start up, hydraulic loads on the engine can be very high. These loads can overtax the engine starter and engine battery capacity. In addition, during on/off concrete pumping cycles while equipment of the concrete hoses are being moved the engine RPM is reduced to idle speeds to increase engine longevity and reduce fuel consumption. When the concrete pump is actuated from these off cycles the loads are influenced by latent pressure in the drive system and the inertia involved in moving concrete from a resting position. Often the latent loads are sufficient enough to cause the engine to lug or stall. Over time these loads on the engine can cause damage to the engine itself, requiring repair or replacement.
The operational theory of said concrete pumps is fairly simple, and most failures modes are caused by loose wiring connections, broken wires, or faulty solenoids. This allows troubleshooting of wiring circuits or the replacement of solenoids to be carried out by pump operators already on the job site. The difficult part of maintaining the pumps is troubleshooting and fault analysis, which often requires trained technicians. What is needed in the industry is a way to automate the troubleshooting process to allow personnel on-site to quickly establish the cause of a failed pump and carry out appropriate maintenance procedures before the concrete in the pump system hardens.